Answer:
3. turns pink and is basic
Explanation:
Phenolphthalein is a pH indicator that remains colorless in acidic solutions, but in basic solutions it turns pink at a pH equal to 10.
Phenolphthalein is a weak acid that loses H+ cations in solution. The phenolphthalein molecule is colorless, while the phenolphthalein-derived anion is pink. When a base is added, phenolphthalein loses H+, forming the anion and causing it to turn pink. The color change cannot be explained only on the basis of deprotonation, a structural change occurs with the appearance of a ketoenolic tautomerism.
This may help you
Use an arbitrary mass, 100 g is an easy number to work with.
60% of 100 g is 60 g, there are two A's. Each A is 30 g
40 g is B, and there is only one, so B is 40 g.
<span>A<span>B2</span></span>, would have a mass of 30 g + 2*40 g = 110 g
The new percent by mass composition of A is: <span><span><span>30g</span><span>110g</span></span>∗100%=27.3%</span>
The new percent by mass composition of B is: <span><span><span><span>80g</span><span>110g</span></span>∗100%=72.7%</span></span>
Answer:
Q = 4019.4 J
Explanation:
Given data:
Mass of ice = 20.0 g
Initial temperature = -10°C
Final temperature = 89.0°C
Amount of heat required = ?
Solution:
specific heat capacity of ice is 2.03 J/g.°C
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
ΔT = 89.0°C - (-10°C)
ΔT = 99°C
Q = 20.0 g ×2.03 J/g.°C × 99°C
Q = 4019.4 J
Answer: it gets inside the air and then it infects the air's resourses
Explanation:
Answer:
It's a soft metal, reactive and with a low melting point, with a relative density of 0,97 at 20ºC (68ºF)
